<field name="channel_id" invisible="1"/>
<field name="subjects" invisible="1"/>
<field name="needaction_pending" invisible="1"/>
+ <field name="message_state" invisible="1"/>
+ <button string="Mark read" type="object"
+ attrs="{'invisible': ['|', ('needaction_pending', '=', False), ('message_state', '=', True)]}"
+ icon="terp-mail-message-new" name="message_check_and_set_read" />
+ <button string="Mark unread" type="object"
+ attrs="{'invisible': ['|', ('needaction_pending', '=', True), ('message_state', '=', False)]}"
+ icon="terp-mail_delete" name="message_check_and_set_unread" />
</tree>
</field>
</record>